1. Field of the Invention
The present invention relates to the field of tools for servicing oil well drilling equipment, and more particularly, for tools that remove rotating head rubbers from drill pipe.
2. Description of the Related Art
Although there are numerous devices for manipulating drill pipe that are the subject of existing patents or patent applications, none of these devices is similar to the present invention in terms of structure or function.
U.S. Pat. No. 2,690,847 (Crookston, 1954) discloses an air-powered device for positioning pipe in a drilling derrick. Compressed air is used to power air pistons and a chain drive mechanism that operate mechanical arms. The device is designed to catch and maneuver a stand of drill pipe as it is being moved from a drill rack to the center of a derrick.
U.S. Pat. No. 6,868,923 (Mitchell, 2005) discloses a portable pipe support apparatus that supports the weight of a pipe string in a borehole when pipe is being installed or removed from the drill string, wherein a pipe connection is supported at waist height to an operator. The purpose of the invention is to allow the operator to manually couple or uncouple pipes while working in an upright position, thereby avoiding the necessity for the operator to repeatedly stoop over or bend down, as occurs when the pipe connections are at ground level. The device is designed to attach to the trailer hitch of a vehicle or, alternately, rest on the ground. Unlike the present invention, the device is designed to support only downward forces (caused by the weight of the drill string) and is not designed to withstand lifting forces that occur when a rotating rubber element is stripped away from a section of drill pipe by raising the pipe. The device does not comprise clamps or other mechanisms to attach the device to a stationary pipe string for support.
U.S. Patent Application No. 2005/0061548 (Hooper et al.) discloses a powered, remotely controlled apparatus for positioning and stabbing drill pipe and well casing in a drilling rig derrick. The invention comprises a jointed articulating boom that pivots about the vertical and horizontal axes and a pipe gripper having arcuate jaws. The invention is powered by pressurized hydraulic fluid. The apparatus is typically mounted near the top of a derrick. The device is designed to assist in the lateral movement of pipe such as casing back and forth from a storage rack on the side of a derrick to the center of the drill floor and is not designed to strip rotating head rubbers from drill pipe.
U.S. Patent Application No. 2015/0075814 (Gerwing et al.) discloses a device fir positioning drill pipe equipment, such as power tongs on a rig floor. The invention provides for horizontal positioning of the equipment with no corresponding vertical movement of the equipment. The invention comprises three moveable arms that are preferably powered hydraulically or pneumatically. The invention is not designed to strip rotating head rubbers from drill pipe.